MainType depends on system-level support for all font types, either from the operating system, Adobe Type Manager Deluxe (no longer available) or Adobe Type Manager Light (ATM Light). More information about ATM Light (a free font utility from Adobe) can be found here:http://www.adobe.com/products/atmlight/main.html

Because Windows 95/ 98/ ME and NT 4.0 have no built-in support for PostScript Type 1 fonts and OpenType fonts, ATM (Light) is required when you want support for these fonts.